Name:
Cotylorhynchus
(Cup snout).
Phonetic: Coe-tih-low-rin-kus.
Named By: John Willis Stovall - 1937.
Classification: Chordata, Synapsida, Pelycosauria,
Caseasauria, Caseidae.
Species: C. romeri (type), C.
bransoni, C.
hancocki.
Type: Herbivore.
Size: 6 meters long.
Known locations: USA, Oklahoma, Texas.
Time period: Kungurian to Roadian of the Permian.
Fossil representation: Many individuals are known.
Although
similar to Casea,
Cotylorhynchus was considerably
larger and at six
meters long, represents the largest known caseid pelycosaur.
This large
size was
its best defence against the known predators of the time which were all
much smaller than Cotylorhynchus, even the largest
example of the
fearsome Dimetrodon
was still only half its size.
the
massive bulk of Cotylorhynchus was not just for
defence, it also housed
the large digestive organs that were required for getting the maximum
amounts of nutrients from the plants that it ate. The great size also
allowed for broad shoulders and powerful muscles that it is thought
allowed Cotylorhynchus to dig up additional parts
like plant roots.
The
hands (bearing in mind that Cotylorhynchus was in
fact quadrupedal) on
the forearms are not only strongly built, they also show a great deal
of dexterous control, further indicating that Cotylorhynchus
had to dig
for additional food to support its large size.
Although
the skull looks undersized for such a large animal, it still has large
fenestra, especially for the nostrils. This may indicate that
Cotylorhynchus had a highly developed sense of smell
that in a
herbivore would presumably help it find food items that were hidden
from sight. Again this points to Cotylorhynchus
possibly digging for
food items, perhaps in a similar way that pigs and some dogs today are
used to sniff out truffles.
Further reading
The San Angelo Formation, Permian of Texas, and its Vertebrates. -
Journal of Geology 61(5):389-423. - E. C. Olson & J. R.
Beerbower - 1953.
- Permian vertebrates from Oklahoma and Texas. Part I.—Vertebrates from
the Flowerpot Formation, Permian of Oklahoma. Oklahoma Geological
Survey, Circular 59:5-48 - E. C. Olson & H. barghusen - 1962.
- The Postcranial Skeleton of the Giant Permian Pelycosaur
Cotylorhynchus romeri. - Bulletin of the Museum of
Comparative Zoology
135 - J. Willis Stovall, Llewellyn Price & Alfred Romer - 1966.